/*
 * Copyright (c) 2007, 2015, Oracle and/or its affiliates. All rights reserved.
 * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
 */
/*
 * Copyright 2001-2004 The Apache Software Foundation.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
/*
 * $Id: NodeType.java,v 1.2.4.1 2005/09/05 11:24:25 pvedula Exp $
 */

package com.sun.org.apache.xalan.internal.xsltc.compiler.util;

import com.sun.org.apache.bcel.internal.generic.BranchHandle;
import com.sun.org.apache.bcel.internal.generic.CHECKCAST;
import com.sun.org.apache.bcel.internal.generic.ConstantPoolGen;
import com.sun.org.apache.bcel.internal.generic.GETFIELD;
import com.sun.org.apache.bcel.internal.generic.GOTO;
import com.sun.org.apache.bcel.internal.generic.IFEQ;
import com.sun.org.apache.bcel.internal.generic.ILOAD;
import com.sun.org.apache.bcel.internal.generic.INVOKEINTERFACE;
import com.sun.org.apache.bcel.internal.generic.INVOKESPECIAL;
import com.sun.org.apache.bcel.internal.generic.ISTORE;
import com.sun.org.apache.bcel.internal.generic.Instruction;
import com.sun.org.apache.bcel.internal.generic.InstructionList;
import com.sun.org.apache.bcel.internal.generic.NEW;
import com.sun.org.apache.bcel.internal.generic.PUSH;
import com.sun.org.apache.xalan.internal.xsltc.compiler.Constants;
import com.sun.org.apache.xalan.internal.xsltc.compiler.FlowList;
import com.sun.org.apache.xalan.internal.xsltc.compiler.NodeTest;

/**
 * @author Jacek Ambroziak
 * @author Santiago Pericas-Geertsen
 */
public final class NodeType extends Type {

  private final int _type;

  protected NodeType() {
    this(NodeTest.ANODE);
  }

  protected NodeType(int type) {
    _type = type;
  }

  public int getType() {
    return _type;
  }

  public String toString() {
    return "node-type";
  }

  public boolean identicalTo(Type other) {
    return other instanceof NodeType;
  }

  public int hashCode() {
    return _type;
  }

  public String toSignature() {
    return "I";
  }

  public com.sun.org.apache.bcel.internal.generic.Type toJCType() {
    return com.sun.org.apache.bcel.internal.generic.Type.INT;
  }

  /**
   * Translates a node into an object of internal type <code>type</code>.
   * The translation to int is undefined since nodes are always converted
   * to reals in arithmetic expressions.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      Type type) {
    if (type == Type.String) {
      translateTo(classGen, methodGen, (StringType) type);
    } else if (type == Type.Boolean) {
      translateTo(classGen, methodGen, (BooleanType) type);
    } else if (type == Type.Real) {
      translateTo(classGen, methodGen, (RealType) type);
    } else if (type == Type.NodeSet) {
      translateTo(classGen, methodGen, (NodeSetType) type);
    } else if (type == Type.Reference) {
      translateTo(classGen, methodGen, (ReferenceType) type);
    } else if (type == Type.Object) {
      translateTo(classGen, methodGen, (ObjectType) type);
    } else {
      ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
          toString(), type.toString());
      classGen.getParser().reportError(Constants.FATAL, err);
    }
  }

  /**
   * Expects a node on the stack and pushes its string value.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      StringType type) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    switch (_type) {
      case NodeTest.ROOT:
      case NodeTest.ELEMENT:
        il.append(methodGen.loadDOM());
        il.append(SWAP); // dom ref must be below node index
        int index = cpg.addInterfaceMethodref(DOM_INTF,
            GET_ELEMENT_VALUE,
            GET_ELEMENT_VALUE_SIG);
        il.append(new INVOKEINTERFACE(index, 2));
        break;

      case NodeTest.ANODE:
      case NodeTest.COMMENT:
      case NodeTest.ATTRIBUTE:
      case NodeTest.PI:
        il.append(methodGen.loadDOM());
        il.append(SWAP); // dom ref must be below node index
        index = cpg.addInterfaceMethodref(DOM_INTF,
            GET_NODE_VALUE,
            GET_NODE_VALUE_SIG);
        il.append(new INVOKEINTERFACE(index, 2));
        break;

      default:
        ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
            toString(), type.toString());
        classGen.getParser().reportError(Constants.FATAL, err);
        break;
    }
  }

  /**
   * Translates a node into a synthesized boolean.
   * If the expression is "@attr",
   * then "true" is pushed iff "attr" is an attribute of the current node.
   * If the expression is ".", the result is always "true".
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      BooleanType type) {
    final InstructionList il = methodGen.getInstructionList();
    FlowList falsel = translateToDesynthesized(classGen, methodGen, type);
    il.append(ICONST_1);
    final BranchHandle truec = il.append(new GOTO(null));
    falsel.backPatch(il.append(ICONST_0));
    truec.setTarget(il.append(NOP));
  }

  /**
   * Expects a node on the stack and pushes a real.
   * First the node is converted to string, and from string to real.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      RealType type) {
    translateTo(classGen, methodGen, Type.String);
    Type.String.translateTo(classGen, methodGen, Type.Real);
  }

  /**
   * Expects a node on the stack and pushes a singleton node-set. Singleton
   * iterators are already started after construction.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      NodeSetType type) {
    ConstantPoolGen cpg = classGen.getConstantPool();
    InstructionList il = methodGen.getInstructionList();

    // Create a new instance of SingletonIterator
    il.append(new NEW(cpg.addClass(SINGLETON_ITERATOR)));
    il.append(DUP_X1);
    il.append(SWAP);
    final int init = cpg.addMethodref(SINGLETON_ITERATOR, "<init>",
        "(" + NODE_SIG + ")V");
    il.append(new INVOKESPECIAL(init));
  }

  /**
   * Subsume Node into ObjectType.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      ObjectType type) {
    methodGen.getInstructionList().append(NOP);
  }

  /**
   * Translates a node into a non-synthesized boolean. It does not push a
   * 0 or a 1 but instead returns branchhandle list to be appended to the
   * false list.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateToDesynthesized
   */
  public FlowList translateToDesynthesized(ClassGenerator classGen,
      MethodGenerator methodGen,
      BooleanType type) {
    final InstructionList il = methodGen.getInstructionList();
    return new FlowList(il.append(new IFEQ(null)));
  }

  /**
   * Expects a node on the stack and pushes a boxed node. Boxed nodes are represented by an instance
   * of <code>com.sun.org.apache.xalan.internal.xsltc.dom.Node</code>.
   *
   * @see com.sun.org.apache.xalan.internal.xsltc.compiler.util.Type#translateTo
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      ReferenceType type) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();
    il.append(new NEW(cpg.addClass(RUNTIME_NODE_CLASS)));
    il.append(DUP_X1);
    il.append(SWAP);
    il.append(new PUSH(cpg, _type));
    il.append(new INVOKESPECIAL(cpg.addMethodref(RUNTIME_NODE_CLASS,
        "<init>", "(II)V")));
  }

  /**
   * Translates a node into the Java type denoted by <code>clazz</code>.
   * Expects a node on the stack and pushes an object of the appropriate
   * type after coercion.
   */
  public void translateTo(ClassGenerator classGen, MethodGenerator methodGen,
      Class clazz) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();

    String className = clazz.getName();
    if (className.equals("java.lang.String")) {
      translateTo(classGen, methodGen, Type.String);
      return;
    }

    il.append(methodGen.loadDOM());
    il.append(SWAP);                // dom ref must be below node index

    if (className.equals("org.w3c.dom.Node") ||
        className.equals("java.lang.Object")) {
      int index = cpg.addInterfaceMethodref(DOM_INTF,
          MAKE_NODE,
          MAKE_NODE_SIG);
      il.append(new INVOKEINTERFACE(index, 2));
    } else if (className.equals("org.w3c.dom.NodeList")) {
      int index = cpg.addInterfaceMethodref(DOM_INTF,
          MAKE_NODE_LIST,
          MAKE_NODE_LIST_SIG);
      il.append(new INVOKEINTERFACE(index, 2));
    } else {
      ErrorMsg err = new ErrorMsg(ErrorMsg.DATA_CONVERSION_ERR,
          toString(), className);
      classGen.getParser().reportError(Constants.FATAL, err);
    }
  }

  /**
   * Translates an object of this type to its boxed representation.
   */
  public void translateBox(ClassGenerator classGen,
      MethodGenerator methodGen) {
    translateTo(classGen, methodGen, Type.Reference);
  }

  /**
   * Translates an object of this type to its unboxed representation.
   */
  public void translateUnBox(ClassGenerator classGen,
      MethodGenerator methodGen) {
    final ConstantPoolGen cpg = classGen.getConstantPool();
    final InstructionList il = methodGen.getInstructionList();
    il.append(new CHECKCAST(cpg.addClass(RUNTIME_NODE_CLASS)));
    il.append(new GETFIELD(cpg.addFieldref(RUNTIME_NODE_CLASS,
        NODE_FIELD,
        NODE_FIELD_SIG)));
  }

  /**
   * Returns the class name of an internal type's external representation.
   */
  public String getClassName() {
    return (RUNTIME_NODE_CLASS);
  }

  public Instruction LOAD(int slot) {
    return new ILOAD(slot);
  }

  public Instruction STORE(int slot) {
    return new ISTORE(slot);
  }
}
